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How to Solve Common Faults in Plastic Granulators?

Jul. 11, 2019

Common faults in plastic granulators are that the main motor torque is too high or too low, the friction clutch is faulty, and the granulator screw section is faulty. As a Hopper Dryer Supplier, let's talk to you.

[Main motor torque is too high]

Analysis of the cause: The oil lubrication system is faulty, the main motor and the gearbox are in poor alignment, and the motor and clutch vibration will damage the main motor bearing, resulting in excessive torque. Excessive feed loading or poor material melting can also cause excessive torque in the main motor.

Solution: Regularly check and clean the lubricating oil system, and measure the main motor bearing with a vibration measuring instrument and an infrared thermometer to form a trend chart. If the trend value is exceeded, determine whether the main motor idle current value or power value exceeds the specified value and determine whether the bearing should be replaced. Regularly check the alignment between the main motor output shaft and the gearbox input shaft. The alignment must be checked after three months of initial or replacement bearing operation. Perform electrical test checks to determine the cause of the rotor imbalance; perform a vibration speed test on the clutch and re-adjust the dynamic balance if the specified value is exceeded. Regularly check the heating and cooling system of the cylinder to ensure that the material is evenly melted by heat. If the extruder motor starts instantaneously, the main motor power curve and the melt pressure curve increase instantaneously, indicating that the feeding amount of the feeding system is too large, and the feeding amount should be reduced.

Plastic Granulator

[Main motor torque is too low]

Analysis of the cause: Failure of the feeding system causes the twin-screw idle to cause the main motor torque to be too low.

Solution: Check whether the additive system or the main material cutting system is faulty and clean the plastic granulator plugging point.

[Friction clutch failure]

Cause analysis: 1. The main motor starting voltage is too low. 2. The instrument wind pressure of the friction clutch is too high; 3. The speed difference of the friction clutch is too large

Remedy: When starting the main motor, avoid the peak of power consumption and reduce the feeding load. The interval between restarts is as short as 30 minutes. In summer, when the main motor is restarted more than twice, the interval should be extended. Use a fan to force a cooldown. Sweep with the instrument wind and wipe the surface of the friction plate and the friction plate with a rag. Check if the air pressure value matches the friction disc to the friction plate.

[Pelletizer screw process section failure]

Analysis of the cause: the melt pressure before and after the throttle valve is too high; the melt pressure of the machine head is too high; the melt pressure difference before and after the change of the screen is too large; the rotation of the driving valve is faulty.

Solution: If the extruder motor starts, the main motor power curve and the melt pressure curve increase, indicating that the feeding amount of the feeding system is too large, and the feeding amount should be reduced.

For more information on Plastic Granulator, please visit our website, https://www.aumax-plast.com

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